Four Techniques for Retreatment After Excimer Laser Photorefractive Keratectomy

BACKGROUND: Retreatment should be considered for patients unsatisfied because of undercorrection and/or haze following excimer laser photorefractive keratectomy (PRK) for myopia. It is unclear if any specific type of retreatment is superior to another, especially in terms of post-treatment myopic shift and haze. METHODS: After a mean follow-up of 12.4 +/- 5.5 months, we retreated 10 eyes by four different techniques following failed PRK: only PRK, PRK with phototherapeutic keratectomy (PTK), only PTK, and mechanical scraping. RESULTS: After a mean follow-up of 11.4 +/- 7.8 months (range, 6 to 28 mos), the final mean refraction was 2.40 +/- 2.00 D (range, 0 to -6.00 D). Corneal clarity improved in 70% of eyes. The mean uncorrected visual acuity improved from 20/200 to 20/40. Of the four retreatment techniques, only scraping proved ineffective, due to unstable outcome. CONCLUSIONS: PRK alone, PRK with PTK, and PTK alone appeared safe and effective methods of retreatment, with no worsening of corneal clarity.